Photographic disk



May 6, 1930. D. A. M COWAN PHOTOGRAPHIC DISK Filed Dec'. 17 1927 [r2 l/en ion Patented Ma 6, 1930 DAVID A. MCGOWANQOF TORONTO, ONTARIO, CANADA.

PI -IOTOGRAPHIG DISK-V Application filed Dec ember17, 1927. Serial no..24;o,so1.

The principal objects of this invention are,

to devise a photographic disk in which the sensitized surface is surrounded by a raised rim which protects it from being marred and which serves eflectively in the production of V the photograph vas a means for retaining the a developing solution in contact with the sensitized surface and also as a protecting or holdlng element for a mirror surface on the reverse side of the disk. I

The principal features of the invention'consist in the novel construction of a sheet metal j disk whereby a photographic or reflecting surface is surrounded by a raised beadededge flange and said flange may be utilized to embrace and secure a supplementary disk on the reverse side of'the photographic. surface.

In the drawings, Figure 1 is front plan 0 viewof my device. 1

side of the disk.

Figure 3 is a cross sectional view. This invention has been particularly devised for use in automatic photographing machine and it consists ofa disk of thin sheet metal preferably non-corrosive which V is stamped with a central circular depressed portion 1 which may be slightly convexed as shown to add strength and to enhance the.

appearance. The raised perimeter 2 is curled in toward the back of the disk to form a beaded edge 3.

The raised raised centreof the convexed portion l'form- 5 ing a rim which will retain a developing fluid.

so asto cover the central depressed areaandz it also forms an eifective protecting flange to keep the central area from contact with other surfaces such asthe sides of a bag or the lin- 0 ing of a pocket,-thusretaining the surface on which a photograph is produced from being marred. p

The reverse side of the disk is preferably covered with a disk 5, the edge 4t of which is flanged to fit snugly around the edge of the:

. p on, saidfluidbeing retained by the flanged Figure 2 is a plan view of the reverse portion 2 extends above the depressed portion 1 and this disk is rigidly secured in place by theinturnededge of the bead3. The outer "surface of the disk 5 is arranged below the plane of the outer surface 6 of the head 3 and it is thus protected in a manner similar to the surface of the portion 1.

The disk 5 may be formedofa suitable noncorrosive metal which willtake a highpo-lish or a silvered glass disk may beused'instead of a metal disk.

It may befound desirable to utilize the depressed surface 1 as a mirror and the surface I of the disk5 as a photographic surface. In either case the metal surface is coatedwith a sensitivephotographic material which after being properly exposed to light through a Y photographic lens, may be developed by placing a small quantity of developing fluid therebead surrounding same.

.chine presents a strong and rigid edge to co-operate withthe automaticmechanism.

The article whencompleted presents a very attractive appearance and may be carried for a considerabl'e time without being marred.

' I What I claim as myinvention is LA photographic disk formed of sheet metal having the marginal edge portion displaced from the plane of the disk, and a rigid bead formation formed at the outward edge extremity of said displaced marginal edge portion. a

2. A photographic disk formed of sheet metal "having a laterally flanged perimeter terminating ;in a rolled edge,.and a central sensitized plane portion offset from the flanged portion to a point. intermediate of the depth of the rolled portion.

- 3; A photographic diskformed of polished sheet metal having a central circular portion of convexed form, a laterally ofiset flange formed with abeaded edgeextremity, and a circular diskhaving its edge secured under theledge of said beaded flange and having a sensitized plane surface dis osed out of align-1 V ment with the edge of the ead formation at its ip'oint of contact with said circular disk. 4:. A photographic disk formed ofrsheet metal having the marginal edge ortion displaced laterally to one side out 0 alignment With the surface to besenslitized, the outward edge portions of said marginal edge portion being rolled inwardly to bring the edge there of into close contact-With: the'mar ginal edge portion on the sensitized side of the disk and out 01f alignment with the latter.

' ia v leiv MCGQWANJ 

